Mushfiqur, who was wearing a helmet, slowly went to the ground then rolled over onto his back and was immediately attended to by medical staff from both teams before paramedics with an on-site ambulance rushed onto the field.
The 29-year-old, who was deemed fit enough to bat on the final day of the first test after X-rays cleared him of broken fingers, was moving his arms and legs as he responded to treatment following the incident in the first session.
Team mate Tamim Iqbal told reporters that Mushfiqur was fine and that he had been taken for checks as a precaution. Television reported the wicketkeeper was talking and had told them to tell his family in Bangladesh he was okay.
Mushfiqur, who scored 159 in the first innings, was on 13 when he left the field. Play was held up for about 15 minutes.
Bangladesh collapsed in their second innings to 160 for nine, leaving New Zealand needing 217 runs from a minimum of 57 overs for an unlikely victory after the visitors scored 595 for eight declared in their first innings.
Imrul Kayes, who retired hurt on 24 on Sunday after he suffered a hip injury, came back at the fall of the seventh wicket but he could barely move and added 12 runs before Subashis Roy was bowled for a duck by Trent Boult.
Sabbir Rahman top-scored with 50.
(Reporting by Greg Stutchbury; Editing by Peter Rutherford)
